Introducing the Eulalia and new Polana asteroid families: Re-assessing primitive asteroid families in the inner Main Belt
Abstract
The so-called Nysa-Polana complex of asteroids is a diverse and widespread group studied by Cellino et al. (Cellino, A., Zappala, V., Doressoundiram, A., di Martino, M., Bendjoya, P., Dotto, E., Migliorini, F., 2001. Icarus 152, 225-237) as a dynamically linked asteroid family.
It carries the name of two asteroids because it appears to be two overlapping families of different asteroid taxonomies: (44) Nysa is an E-type asteroid with the lowest number in the midst of a predominantly S-type cluster and (142) Polana is a B-type asteroid near the low-albedo B-and C-type cluster. The latter has been shown to be a very important source of primitive near Earth asteroids.
Using the data from the Wide-field Infrared Survey Explorer (WISE) mission we have re-analyzed the region around the Nysa-Polana complex in the inner Main Belt, focusing on the low-albedo population.